Cross Connection Program


What is a cross connection?

A cross connection is a direct or potential connection between any part of the public water supply system and a source of contamination or pollution. The most common form of cross connection is a garden hose, which is easily connected to the public water system and can be used to apply a variety of potentially dangerous substances, including chemicals and fertilizer. Other common cross connections include dishwashers, toilets, pressure washers, boilers, pools and lawn sprinkler systems.

How does contamination occur?

Water normally flows in one direction, from the public water system through the customer's cold or hot water plumbing system to a faucet or other plumbing fixture. Under certain conditions, water can flow in the reverse direction. This is known as backflow, and it occurs when back-siphoning or back pressure is created in a water line.

  • Backpressure may be created when a source of pressure, such as a pump, boiler, or other building creates pressure greater than that supplied from the water distribution system. This may force water to reverse direction.
  • Back-siphoning may occur when there is a drop in the supply pressure of the water distribution system. This can be caused by a water line break, water main repair, or during a rapid withdrawal of water from a fire hydrant. This creates a vacuum, which may pull or siphon contaminants and pollutants into the drinking water supply.

Residential Water User Hazards

Non-residential Water Users

What Is a Cross Connection Control Program?

This is a combined cooperative effort between plumbing and health officials, municipalities, and property owners to establish and administer guidelines for controlling cross connections and ensure their enforcement so that the public drinking water supply is protected both in the village distribution system and within buildings to the point of use.

Our program consists of the following components:

  • Annual testing: All backflow prevention assemblies will be tested once a year by certified testers.
  • Cross connection survey: All industrial, commercial, and institutional facilities' plumbing systems will be inspected to determine if cross connections exist.
  • Installation of protective devices: Backflow prevention devices or assemblies will need to be installed where known unprotected cross connections exist.
  • Public education program: During a cross connection survey, an informational brochure will be given to our water customers.


Cross connection control program questions can be directed to Village of Menomonee Falls Utilities Superintendent Tom Dimoff by email, or at 262-532-4808.